Japan Earthquake: Nuclear Plants at Fukushima Daiichi

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The Fukushima Daiichi nuclear plant is facing significant challenges following the earthquake, with reports indicating that reactor pressure has reached dangerous levels, potentially 2.1 times capacity. TEPCO has lost control of pressure at a second unit, raising concerns about safety and management accountability. The reactor is currently off but continues to produce decay heat, necessitating cooling to prevent a meltdown. There are conflicting reports about an explosion, with indications that it may have originated from a buildup of hydrogen around the containment vessel. The situation remains serious, and TEPCO plans to flood the containment vessel with seawater as a cooling measure.
  • #12,631
nikkkom said:
Well, Unit 4 is not that bad. It is not as contaminated as the other units.
They already cut off a significant part of upper, damaged levels of the building. It seems to be progressing nicely. Replacing the crane and other equipment, vacuuming the pool and starting to pull assemblies out would take 2 years from today?

I don't think they will replace the crane.
 
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  • #12,632
zapperzero said:
I don't think they will replace the crane.

Perhaps only the FHM.
 
  • #12,633
I would guess it is in Tepco's interest to close the chapter of unit 4 as soon as possible to be able to focus on other important and difficult tasks (I see plenty of them...). And the more time passes, the higher is the risk that new problems from the pools might arise.

If they tell me end of 2012, ok. But end of 2013?
They know already for one year that they will have to get the stuff out of the pools, so it's not new to them. Maybe it is the debris in the pool or the water quality? But if so, what will be then at units 1 and 3, with half of the reactor buildings lying in the pools? Or perhaps the fuel bundles are simply still too hot to be handled in that way?

Would be interesting to know.
 
  • #12,634
Yamanote said:
What is the reason for waiting so long? Is it not possible to pick the stuff out right now?

They have to (had to?) repair the common pool crane, then improve the reliability of the power source for the common pool.
It's also possible that some room must be made or arranged in the common pool, 1500 bundles of fuel is some decent amount.

On unit 4 top level they have to repair and secure the FHM machinery: rails, crane and so.

Arrange and transfer some transfer casks.

Make up plans, revise and and get permissions for the process. Train staff.

Run the work on the other units.

My personal feeling that if they can then they will jump as soon as possible and don't wait for the schedule, but actually the schedule looks OK for me - no hurry, and yet not lazy...

Ps.: as I know fuel bundles must wait 3-5 years after usage before they are ready for transfer in transfer casks. Some fuel in U4 pool might be ready for transfer right now, but for some even the end of 2013 might be too early. I don't know if this limit can be tricked by putting less fuel in a cask than it's capacity...
 
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  • #12,635
Rive said:
My personal feeling that if they can then they will jump as soon as possible and don't wail for the schedule, but actually the schedule looks OK for me - no hurry, and jet not lazy...

At first Tepco wanted to take one more year, but this was refused by the government :

tsutsuji said:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20111109/1400_kouteihyo-shiji.html and http://www3.nhk.or.jp/news/genpatsu-fukushima/20111109/1650_30nen.html The ministers of Industry (Edano) and Nuclear accident (Hosono) have asked Tepco to prepare a schedule where spent fuel pool fuel removal is started within 2 years after completion of step 2. This is one year earlier than recommended in the report from the middle and long term commission that was completed on 9 November.
 
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  • #12,636
triumph61 said:
Perhaps only the FHM.

FHM capacity is a few hundred pounds. Caskes weigh several tonnes. FHM has fine control needed to prevent damage to a fuel bundle. That is not something easy to achieve with a heavy lift crane.
 
  • #12,637
NUCENG said:
FHM capacity is a few hundred pounds. Caskes weigh several tonnes. FHM has fine control needed to prevent damage to a fuel bundle. That is not something easy to achieve with a heavy lift crane.

Thats right, but the FHM can take the Fuel into the Cask.
 
  • #12,638
SpunkyMonkey said:
This may be the missing Unit 3 refueling crane fallen into the spent-fuel pool as seen in an April, 14 2011 image here:

SFP3_April14_isCraneIn_small.jpg


The graphic shows similar objects between this piece of wreckage in the Unit 3 pool and the intact Unit 4 refueling crane. It also shows a similar spatial conjunction of similar objects, and this meta-similarity makes me confident we're looking at Unit 3's refueling crane.

There are many pre-tsunami photos of the refueling crane here.

Why isn't the proposed refueling crane also bright green? My guess is that the fire that blasted out the south side over the pool and thus onto the crane scorched off the paint.

I feel this area of the SFP3 is a really good candidate for harbouring the missing FHM and its supporting bridge, however in the collection of wreckage I've found nothing really strikingly looking like it's matching parts of the FHM. The best I'd got is the green platform like object that is located submersed, just about where you have written 'railing?' in your photo montage. I think you are right that we shouldn't necessarily be looking for something standing in the original bright green colour.

From the same video source (taken by the crane camera on 18th of april 2011), I have a possible ID of the ladder that used to lead to the NW corner of the bridge which used to carry the FHM3.

If identified correctly, this ladder did end up not too far from its original position, where it got entangled in a fallen cross beam from the roof construction.

Below is a montage of an original photo of the ladder on the intact FHM bridge, some screen shots from the crane camera video, and a Tepco released photo from April 14th of the same ladder. I note the wrecked ladder has the same number, and same unusual positioning of steps, and it has what would represent the right hand rail still attached. While the left hand rail is missing, the Tepco released photo does display in a correct position what would represent remains of the two bolts that held it.

Unit3_NW_ladder_FHM_bridge.jpg
 
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  • #12,639
tsutsuji said:
At first Tepco wanted to take one more year, but this was refused by the government :

Fair to say, the environment in the SFP4 does remain unpleasantly corrosive (and the developed murkiness and the apparent caking on top of the assemblies might already have something to do with this.) Over a further 2+ year timeline, the prolonged corrosion could jam the assemblies in the racks, making it more difficult to remove them. I wonder how much aluminium alloy is in the pool, anybody knows?
 
  • #12,640
I thought maybe some of you might find this article interesting, even though it's - thankfully - not of great consequence as far as what's going on at Daichi these days. It's about a cover-up of a defect in the reactor vessel of reactor 4.

http://www.bloomberg.com/news/2011-03-23/fukushima-engineer-says-he-covered-up-flaw-at-shut-reactor.html
 
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  • #12,641
hi @ all

my name is ulli and i come from germany.
(germanium 71 )
i'm the one who made the masses of edited and timelapsed videos from and around fukuground.
mostly i worked with lapsed and captured streams from fukushima.

i'm not a physics-crack, i had studied *soziologie* and learned and worked as a bakerman too, special as a *bio-vollkorn-bäcker*.

and there i only does *reporting* visual moments from the boths streams.
i failed many times with my first optic impressions and that's okay.
because nobody will hurts by my wrong optical impressions and they based just on a single view and not on a nuclear-techno-study from 6 or 7 years.

but as japan/tepco is covering so much of all, included the optics,
i will find day per day more.
since january i didn't abled to work all the recorded stream time out...
there is to much stuff in it.
special @ the last two months.

so please take my posted videos as that what they are:
just an optic reported impression from a subject view or of a meaning of it.

i think that it will be importent for readers who searches some facts from fukuground, that the discussions in the public will be done correctly and fair.


and i didn't tricked on the videos, only sometimes a bit too much effected and too dramatic soundings...

i will give you all a sample from what i talk about.
remember you on the last poolr-video-releases from tepco in the last days.
(they putted them into a wrong frame size, played to fast and also the colors had a touch too much of tepcolors.)
first i fixed the frame-rate on that what it is, 'cause black-framed isn't usefull.
then i slomo them, shapened and color-editings on every video
and voilá,
here we go:
http://youtu.be/JXdPxd14rU8
http://youtu.be/v5-kXSi1ppA

to have a look how the *pool-area* should look normaly:
http://youtu.be/kvfvLEmMlro


i hope my first post cwill explain to you how i working on the streams and that i didn't "press" the stream-records in that sight, in that i wanne have them.

if there will be nothings to be reporten from the streams, perfect.

the endless drama from tepco had learned me
that only no news are good news...


achja,
one more I've got.
there is a new satellite picture from jan 2012, taken by astrium.
http://regard-sur-la-terre.over-blog.com/article-un-an-apres-le-tsunami-retour-a-fukushima-avec-le-satellite-pleiades-101454894.html
but they given it for free only in a 1111 pixel frame...so i made it a bitly bigger with "photo-zoom-pro-3", onto 4444 pixels.
http://www.img-teufel.de/thumbs/PleiadesJaponFukushima18012012copie3215651949cd7djpg.jpg
 
  • #12,642
nuckelchen said:
one more I've got.
there is a new satellite picture from jan 2012, taken by astrium.
http://regard-sur-la-terre.over-blog.com/article-un-an-apres-le-tsunami-retour-a-fukushima-avec-le-satellite-pleiades-101454894.html
but they given it for free only in a 1111 pixel frame...so i made it a bitly bigger with "photo-zoom-pro-3", onto 4444 pixels.
http://www.img-teufel.de/thumbs/PleiadesJaponFukushima18012012copie3215651949cd7djpg.jpg

http://www.flickr.com/photos/geoeyesatelliteimagery/6985103913/lightbox/
 
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  • #12,643
nuckelchen said:
hi @ all

my name is ulli and i come from germany.
(germanium 71 )
i'm the one who made the masses of edited and timelapsed videos from and around fukuground.
mostly i worked with lapsed and captured streams from fukushima.

i'm not a physics-crack, i had studied *soziologie* and learned and worked as a bakerman too, special as a *bio-vollkorn-bäcker*.

and there i only does *reporting* visual moments from the boths streams.
i failed many times with my first optic impressions and that's okay.
because nobody will hurts by my wrong optical impressions and they based just on a single view and not on a nuclear-techno-study from 6 or 7 years.

but as japan/tepco is covering so much of all, included the optics,
i will find day per day more.
since january i didn't abled to work all the recorded stream time out...
there is to much stuff in it.
special @ the last two months.

so please take my posted videos as that what they are:
just an optic reported impression from a subject view or of a meaning of it.

Hello and welcome.

Your slowed down & colour altered videos from things like the reactor 4 fuel pool & reactor well may be of interest to people.

But I would avoid posting much about your TEPCO webcam & TBS feed videos as they do not tend to show anything of scientific interest, they are of little use to this forum. Most of what you will see is related to the weather and other atmospheric affects, nothing to do with the reactors. And the TEPCO webcam suffers from lots of compression artefacts, and if you sometimes see flashing lights in strange places on these videos then you should strongly consider the possibility that its actually a light being reflected off the dome that surrounds the camera.
 
  • #12,644
nuckelchen said:
hi @ all

my name is ulli and i come from germany.
(germanium 71 )

<snip >

achja,
one more I've got.
there is a new satellite picture from jan 2012, taken by astrium.
http://regard-sur-la-terre.over-blog.com/article-un-an-apres-le-tsunami-retour-a-fukushima-avec-le-satellite-pleiades-101454894.html
but they given it for free only in a 1111 pixel frame...so i made it a bitly bigger with "photo-zoom-pro-3", onto 4444 pixels.
[URL]http://www.img-teufel.de/thumbs/PleiadesJaponFukushima18012012copie3215651949cd7djpg.jpg[/PLAIN]




A Jan 2012 image of most the fukuichi site. Interesting view of the extent of the siteworks, tank farms etc.
(Unretouched, unscaled. 3300 x 3300 pixel geoEye satellite)

http://geoeyemediaportal.s3.amazonaws.com/assets/images/gallery/ge1/hires/fukushima_31JAN2012.jpg

March 2011 satellite images I hadnt seen before at this resolution

http://geoeyemediaportal.s3.amazonaws.com/assets/images/gallery/ge1/hires/japan_fukushima_daiichi_after_03_14_11.jpg


Satellite image within minutes of Unit 3 coming apart ( It's a very familiar image but in a higher resolution than I had seen before)
 
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  • #12,645
westfield said:
A Jan 2012 image of most the fukuichi site. Interesting view of the extent of the siteworks, tank farms etc.
(Unretouched, unscaled. 3300 x 3300 pixel geoEye satellite)

The sky on Fuku was quite crowded in those days... very interesting pics! Doubt: is the exhaust stack pipe of R3 missing? It is still there on the pic in which reactor 4 is still intact. Do you believe Tepco removed it, or it was blown away during the explosion of R4?
 
  • #12,646
MadderDoc said:
I feel this area of the SFP3 is a really good candidate for harbouring the missing FHM and its supporting bridge, however in the collection of wreckage I've found nothing really strikingly looking like it's matching parts of the FHM. The best I'd got is the green platform like object that is located submersed, just about where you have written 'railing?' in your photo montage.
I'm more drawn to the green platform-like object where I'm pointing. :smile: So I made this animation especially for you die-hard refueling-trolley deniers :wink:


SFP_April14_craneIn.gif

The 'platform' object I'm talking about is clearly a coherent lattice of heavy-metal beams that appears to be roughly consistent with the I-beam undergirding of a refueling-trolly platform seen above and in this patent (Figure 3C). Not an exact match (and it's not the exact refueling trolley), but it would be the same structural concept. Additionally I also highlight the objects that look like pulleys to me, including another circular-seeming shape I just noticed deeper in. (Fyi, the http://www.tepco.co.jp/en/news/110311/images/110415_1f_4_2.jpg).

Further supporting my impression of identity is that the olive-green color of the Unit-3 refueling crane as it http://www.houseoffoust.com/fukushima/MOXinstall3.jpg when the MOX fuel was loaded appears to be a close match to the olive-green color of both the proposed refueling-crane objects and the larger well-known overhead crane as it appeared late last year in this Tepco video. Those photos showing the refueling crane being olive-green can be found in press reports about the MOX installation.


colorMatch.jpg
So the question for U3-refueling-platform skeptics is: What large olive-green object with a lattice-girder platform and large pulley-like objects was over the fuel pool and was not the olive-green refueling platform?

From the same video source (taken by the crane camera on 18th of april 2011), I have a possible ID of the ladder that used to lead to the NW corner of the bridge which used to carry the FHM3.

Agreed, good ID! Any idea how what seems to be a roof girder became, it seems, co-mingled with a handle railing on the refueling ladder? And what's your source for the April 18 images of the ladder? I've not seen them before and can't find them on Tepco's site.
 
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  • #12,647
SpunkyMonkey said:
So I made this animation

Animations such as this one are difficult to understand, because they leave hardly more than one second to watch each picture. Unlike videos on youtube, there is no pause button.
 
  • #12,648
SpunkyMonkey said:
<..>
Agreed, good ID! Any idea how what seems to be a roof girder became, it seems, co-mingled with a handle railing on the refueling ladder?

Presently I think something heavily hit the roof construction from aloft, pushing and smashing it down close to where the refueling bridge happened to be at the moment. On collision some parts of all parties naturally came loose and got intermingled. For the major part of them, refueling bridge and FHM ended up in the pool. As indicated, that's just my thoughts at the moment:

FHMsearch_Unit3.jpg


SpunkyMonkey said:
And what's your source for the April 18 images of the ladder? I've not seen them before and can't find them on Tepco's site.

It is from some time last year when Tepco released a collection of previously unpublished material, among which were two videos with a total of 50 minutes of capture from the concrete pump camera on April 18. The collection was published only temporarily, timing out by the end of 2011. The link to the collection was posted here, but I believe the link is now dead, (otherwise I should think I'd retained it as a bookmark, which I haven't.) However I retained a.o. grabs of those two videos. Check your mailbox..
 
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  • #12,649
Has this been discussed before? (got to it via ex-skf blog)

http://www.asahi.com/national/update/0603/TKY201106030539.html

"8:30 am on March 12, [tellurium?] was measured and Okuma-machi Namie-machi, Minami Soma City prior to the explosion of Unit 1 and hydrogen vent work" (google translation, sorry, I know no Japanese, this may be very wrong).

This is before even the first attempt at venting, no?
 
  • #12,650
zapperzero said:
Has this been discussed before? (got to it via ex-skf blog)

http://www.asahi.com/national/update/0603/TKY201106030539.html

"8:30 am on March 12, [tellurium?] was measured and Okuma-machi Namie-machi, Minami Soma City prior to the explosion of Unit 1 and hydrogen vent work" (google translation, sorry, I know no Japanese, this may be very wrong).

This is before even the first attempt at venting, no?

Be careful that the Asahi article says "from 8:30 AM to 1:30 PM on March 12". Otherwise your translation is correct.

The data released by the NISA on 3 June 2011 are available at http://www.meti.go.jp/press/2011/06/20110603019/20110603019-2.pdf

I translate the first line of the table page 18/24 :

List of monitoring results in the surroundings of Fukushima Daiichi nuclear power station (atmospheric suspended dust)

Radiation concentrations (Bq/m³):

Code:
Sampling location              Measurement time             I-131  Cs-134 Cs-137 I-132 Te-132 other substances  done by                   page number       notes
Nishihara, Takase, Namie   2011/03/12 08:39 ~ 08:49      37                 1.8      90       73                          Fukushima prefecture          1
See also the maps on pages 18/24 ("page 1") to 22/24 ("page 4")

The yellow lines are marked with "in part already publicly released" in the "notes" column.

In http://www.meti.go.jp/press/2011/06/20110603019/20110603019-3.pdf they explain that the previously released data are those of the 21st report (13 March 2011 at 20:30 PM) and 22nd report (14 March at 7:30 AM) :

In the report of 13 March 2011 at 20:30 PM : http://www.meti.go.jp/press/20110313007/20110313007-4.pdf I find the data measured in Front of Fukushima prefecture Atomic Energy Center at 16:00 on 13 March with 1.7 Bq/m³ of Iodine 131 and ND for Tellurium. English version here : http://www.nisa.meti.go.jp/english/files/en20110313-6.pdf (page 14/15)

In the report of 14 March 2011 at 07:30 AM : http://www.meti.go.jp/press/20110314001/20110314001-3.pdf I find the data measured in Front of Fukushima prefecture Atomic Energy Center at 08:00 ~ 08:10 AM on 13 March : 5.8 Bq/m³ of Iodine 131 and 1.7 Bq/m³ of Tellurium 132.
 
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  • #12,651
zapperzero said:
Has this been discussed before? (got to it via ex-skf blog)

http://www.asahi.com/national/update/0603/TKY201106030539.html

"8:30 am on March 12, [tellurium?] was measured and Okuma-machi Namie-machi, Minami Soma City prior to the explosion of Unit 1 and hydrogen vent work" (google translation, sorry, I know no Japanese, this may be very wrong).

This is before even the first attempt at venting, no?

Yes certainly, but the D/W pressure of unit 1 reached twice design max pressure at 3 am on March 12th, and shortly after that the radiation dose at the site started to increase above normal. Read, shortly after that, abnormal emission started from the plant.

A 10x increase of normal radiation at the main gate was reported to the authorities at about 5 am on the morning of March the 12th, and radiation increased a further 10x during the next hour, where it kept steady until about noon. The wind at the main gate was south-southeasterly during this period.
 
  • #12,652
MadderDoc said:
It is from some time last year when Tepco released a collection of previously unpublished material, among which were two videos with a total of 50 minutes of capture from the concrete pump camera on April 18. The collection was published only temporarily, timing out by the end of 2011. The link to the collection was posted here, but I believe the link is now dead, (otherwise I should think I'd retained it as a bookmark, which I haven't.) However I retained a.o. grabs of those two videos. Check your mailbox..

The ladder can also be seen in less detail shortly after the 6 minute mark on this video:



I concede that it is possible that the FHM is in the pool, although there isn't enough evidence to be sure. I dislike the photo analysis which places too much emphasis on the circular objects being the pulleys, since the material seems like a poor match, although the visual evidence isn't high enough quality to be sure.
 
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  • #12,653
MadderDoc said:
Yes certainly, but the D/W pressure of unit 1 reached twice design max pressure at 3 am on March 12th, and shortly after that the radiation dose at the site started to increase above normal. Read, shortly after that, abnormal emission started from the plant.

A 10x increase of normal radiation at the main gate was reported to the authorities at about 5 am on the morning of March the 12th, and radiation increased a further 10x during the next hour, where it kept steady until about noon. The wind at the main gate was south-southeasterly during this period.

The new factor here is tellurium, which suggests containment damage. Doses could have been increasing from steam escaping the primary coolant loop on the turbine side, or something relatively benign like that.
 
  • #12,654
tsutsuji said:
Be careful that the Asahi article says "from 8:30 AM to 1:30 PM on March 12". Otherwise your translation is correct.

Thank you very much, I will now look at the documents you referenced as well.
 
  • #12,655
zapperzero said:
The new factor here is tellurium, which suggests containment damage. Doses could have been increasing from steam escaping the primary coolant loop on the turbine side, or something relatively benign like that.

I see what you mean, the very short-lived Te-132 would have to come from somewhere having material that had undergone fission quite recently (within at most a few days). Radioactivity as such could in theory have come from other sources.

However, at the time of events it was certainly interpreted as containment failure. While the radioactive dose increased, it was also observed that the overpressurised D/W began to give in and loose pressure, indicating leakage from the D/W to the exterior. Tepco reported this judgement to the authorities, at 5:14 am on March 12th.
 
  • #12,656
SteveElbows said:
The ladder can also be seen in less detail shortly after the 6 minute mark on this video:



I concede that it is possible that the FHM is in the pool, although there isn't enough evidence to be sure. I dislike the photo analysis which places too much emphasis on the circular objects being the pulleys, since the material seems like a poor match, although the visual evidence isn't high enough quality to be sure.


I've seen nothing particular in the pool which to me looks like parts of the FHM itself, however, in the video you linkto, close to the pool gate, I think I can spot something that to me looks like a part of the huge bridge which carried the FHM (The give-away, for the bridge, being the spotting of the rather unique cross-beaming of the structure). So, my current thought, that the FHM is likely in the pool, is rather more based on induction than from observation: thinking, if the FHM bridge has tumbled into the pool, it would seem quite likely that the FHM did too.
 
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  • #12,659
MadderDoc said:
I see what you mean, the very short-lived Te-132 would have to come from somewhere having material that had undergone fission quite recently (within at most a few days). Radioactivity as such could in theory have come from other sources.

However, at the time of events it was certainly interpreted as containment failure. While the radioactive dose increased, it was also observed that the overpressurised D/W began to give in and loose pressure, indicating leakage from the D/W to the exterior. Tepco reported this judgement to the authorities, at 5:14 am on March 12th.

The containment dome seal would as far as I see have started to leak during the night between March 11 and 12. The Mark I dome seal problems due to pressure > 5 bar are as far as I know a well-known issue, and the heat in the containment increases the probability of a seal failure. I still have the view that the hydrogen got to the service floor directly through the dome seal, and this dry route would make it possible for tellurium to escape as well.
 
  • #12,660
Rive said:
http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120322_01-e.pdf

Can somebody please enlighten me about this 'TIP room'?

They are about to get neutron activity readings, or these are new holes (reachable from a relatively low dose area) on the containment for more borescope investigations?

TIP = traversing in-core probe. A gamma detector driven into the core every month or so in order to calibrate the in-core neutron detectors, which slowly burn out in the neutron flux. The TIP is driven from a room next to the containment, routed to one TIP channel at a time, and driven through the channel (=a small pipe) from the bottom of the RPV into the core and back.
 

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